Title: Effect of hot extrusion on the characteristics of an Mg-3.0Zn-0.7Zr-1.0Cu alloy produced by powder metallurgy
Authors: Eacherath Suneesh; Murugesan Sivapragash
Addresses: Department of Production Engineering, Vidya Academy of Science and Technology, Thalakottukara, Thrissur - 680510, Kerala, India ' Department of Mechanical Engineering, PSN College of Engineering and Technology, Tirunelveli, India
Abstract: The present study investigates the effect of hot extrusion on the physical, mechanical, and metallurgical characteristics of an as-extruded Mg-3.0Zn-0.7Zr-1.0Cu alloy. The Mg-3.0Zn-0.7Zr-1.0Cu samples were prepared through a powder metallurgy process which was followed by hot extrusion at 500°C using a suitably designed hydraulic press. Also, the properties of the alloy samples before and after extrusion were compared. The network structure broke down after extrusion and, hence, grains were more refined. This grain refinement is the result of matrix grain rupture, dynamic recrystallisation and the Zenner pinning mechanism. Acceptable tensile properties were noted after extrusion as a result of significant grain refinement and the precipitation of some intermetallic phases. After hot extrusion, the fracture mechanism changed from layer cracking to a mixed mode of cracking with cleaved facets and dimples.
Keywords: magnesium alloy; powder processing; hot extrusion; mechanical properties; dynamic recrystallisation; grain refinement.
DOI: 10.1504/IJMATEI.2020.104791
International Journal of Materials Engineering Innovation, 2020 Vol.11 No.1, pp.51 - 69
Received: 18 Mar 2019
Accepted: 11 May 2019
Published online: 31 Jan 2020 *